Display panel

ABSTRACT

A display panel is provided. The display panel includes a first substrate and a second substrate. The first substrate has a display area and the second substrate is arranged opposite to the first substrate. The display panel further includes a display layer. The display layer is positioned between the first substrate and the second substrate. The display panel also includes a sealant. The sealant is positioned between the first substrate and the second substrate and outside the display area. The sealant has an outline, and at least one portion of the outline is wavy.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 15/335,596,filed on Oct. 27, 2016, which claims the priority of Taiwan PatentApplication No. 104135560, filed on Oct. 28, 2015, the disclosure ofwhich is hereby incorporated by reference herein in its entirety.

BACKGROUND Field of the Invention

The present disclosure relates to an electronic device, and moreparticularly to an electronic display panel with non-rectangular shapeand a method for processing the display panel.

Description of the Related Art

An electronic display is an optoelectronic device that is able totransfer electric signals into visible images so that human beings cansee the information contained in the electronic signals. Recently,liquid-crystal displays, organic electro luminescence displays andlight-emitting diode display have grown in popularity.

Because of their slimness, low power consumption and low radiation,these image-display devices have been widely used in portable electronicdevices such as TV, desktop computers, notebook computers, tablet, andmobile phones, and are even gradually replacing cathode ray tube (CRT)monitors and conventional TVs.

SUMMARY

In accordance with some embodiments of the disclosure, a display panelis provided. The display panel includes a first substrate and a secondsubstrate. The first substrate has a display area and the secondsubstrate is arranged opposite to the first substrate. The display panelfurther includes a display layer. The display layer is positionedbetween the first substrate and the second substrate. The display panelalso includes a sealant. The sealant is positioned between the firstsubstrate and the second substrate and located outside the display area.The sealant has an outline, and at least a portion of the outline iswavy.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the embodiments and the advantagesthereof, reference is now made to the following descriptions taken inconjunction with the accompanying drawings.

FIG. 1 shows a cross-sectional view of a display panel, in accordancewith some embodiments.

FIG. 2 shows a top view of a portion of elements of a display panel, inaccordance with some embodiments.

FIG. 3 shows a schematic view explaining a definition of a manufacturingvariance and a definition of a pitch between node centers, in accordancewith some embodiments.

FIG. 4 shows a flow chart of a method for applying a curved segment of asealant, in accordance with some embodiments.

FIG. 5 shows an enlarged view of a region in FIG. 2 near an intersectionpoint 112, in accordance with some embodiments.

FIG. 6 shows a flow chart of a method for applying a curved segment of asealant, in accordance with some embodiments.

FIG. 7 shows an enlarged view of a region in FIG. 2 near an intersectionpoint 114, in accordance with some embodiments.

FIG. 8 shows a schematic view of a sealant, in accordance with someembodiments.

FIG. 9 shows an image of a display panel observed with a microscope, inaccordance with some embodiments.

FIG. 10 shows an image of a display panel observed with a microscope, inaccordance with some embodiments.

FIG. 11 shows a schematic view of a display panel, in accordance withsome embodiments.

FIG. 12 shows an image of a display panel observed with a microscope, inaccordance with some embodiments.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

The display panel of the present disclosure is described in detail inthe following description. In the following detailed description, forpurposes of explanation, numerous specific details and embodiments areset forth in order to provide a thorough understanding of the presentdisclosure. The specific elements and configurations described in thefollowing detailed description are set forth in order to clearlydescribe the present disclosure. It will be apparent, however, that theexemplary embodiments set forth herein are used merely for the purposeof illustration, and the inventive concept may be embodied in variousforms without being limited to those exemplary embodiments. In addition,the drawings of different embodiments may use like and/or correspondingnumerals to denote like and/or corresponding elements in order toclearly describe the present disclosure. However, the use of like and/orcorresponding numerals in the drawings of different embodiments does notsuggest any correlation between different embodiments. Furthermore, theattached drawings may be drawn in a slightly simplified or exaggeratedway for ease of understanding; the numbers, shapes and dimensionalscales of elements depicted may not be exactly the same as those inpractical implementation and are not intended to limit the presentdisclosure.

It should be noted that the elements or devices in the drawings of thepresent disclosure may be present in any form or configuration known tothose skilled in the art. In addition, the expression “a layer overlyinganother layer”, “a layer is disposed above another layer”, “a layer isdisposed on another layer” and “a layer is disposed over another layer”may indicate not only that the layer directly contacts the other layer,but also that the layer does not directly contact the other layer, therebeing one or more intermediate layers disposed between the layer and theother layer.

In this specification, relative expressions are used. For example,“lower”, “bottom”, “higher” or “top” are used to describe the positionof one element relative to another. It should be appreciated that if adevice is flipped upside down, an element at a “lower” side will becomean element at a “higher” side.

The terms “about” and “substantially” typically mean +/−20% of thestated value, more typically +/−10% of the stated value and even moretypically +/−5% of the stated value. The stated value of the presentdisclosure is an approximate value. When there is no specificdescription, the stated value includes the meaning of “about” or“substantially”.

FIG. 1 shows a cross-sectional view of a display panel 1, in accordancewith some embodiments. In some embodiments, the display panel 1 includesa first substrate 10, a second substrate 20, a display layer 30, and asealant 40. The elements of the display panel 1 can be added or omitted,and the disclosure should not be limited by the embodiment. The firstsubstrate 10 and the second substrate 20 may be a rigid substrate or aflexible substrate. The rigid substrate may comprise but not limit toglass, sapphire or ceramic. The flexible substrate may comprisepolyimide (PI), polyethylene terephthalate (PET), polycarbonate (PC), orother suitable organic materials. The display layer 30 may be liquidcrystal, organic light-emitting diode, or light emitting diode.

The display panel 1 may be a liquid-crystal panel, such as thin filmtransistor panel. Alternatively, the display panel 1 may be a twistednematic (TN) mode liquid-crystal panel, a vertical aligned (VA) modeliquid-crystal panel, an in-plane switching (IPS) mode liquid-crystalpanel, a fringe field switching (FFS) mode liquid-crystal panel, acholesteric mode liquid-crystal panel, a blue phase in-plane switching(IPS) mode liquid-crystal panel, or another suitable liquid-crystalpanel. The display panel 1 may be an organic light-emitting diode (OLED)panel, a light-emitting diode (LED) panel, a micro light-emitting diode(micro LED) panel and a quantum dot (QD) panel.

In some embodiments, the second substrate 20 is spaced apart from thefirst substrate 10 by a distance and covers the first substrate 10. Thedisplay layer 30 is positioned between the first substrate 10 and thesecond substrate 20. The display layer 30 is operated according toelectronic signals from the driving unit (not shown in figures) so as toshow images. The first substrate 10 may be a thin film transistor (TFT)substrate and include a number of pixels and switching elements. Thesecond substrate 20 may be a color filter substrate or a transparentcover substrate. The first substrate 10 or the second substrate 20 maybe equipped with touch functionality.

The sealant 40 is connected between the first substrate 10 and thesecond substrate 20. The sealant 40 may surround the display layer 30.Or, the sealant 40 may not surround the display layer 30 but may beapplied neighboring a portion of the display layer 30. In oneembodiment, the sealant 40 is applied on the first substrate 10 (or thesecond substrate 20) along a path with a rectangular shape ornon-rectangular shape. The path is defined according to the shape of theouter edge of the first substrate 10 (or the second substrate 20).Alternatively, the path is defined according to the shape of the displayarea AA. In one embodiment, the sealant 40 is applied between an edge ofthe first substrate 10 and an edge of the display area AA. In otherwords, the sealant 40 is applied on a non-display area. In oneembodiment, the non-display area is located between an edge of the firstsubstrate 10 and an edge of the display area AA. In one embodiment, thedisplay area AA is an area where display elements for display images arepositioned.

FIG. 2 shows a top view of a portion of the display panel 1, inaccordance with some embodiments. In one embodiment, the first substrate10 is not rectangular, and it includes a number of lateral edges 111,113, and 115 which are consecutively connected to one another. Thelateral edge 111 connects to the lateral edge 113 via an intersectionpoint 112, and the lateral edge 113 connects to the lateral edge 115 viaan intersection point 114. In the embodiment shown in FIG. 2, theincluded angle formed by the two lateral edges 111 and 113 is largerthan the included angle formed by the two lateral edges 113 and 115. Inone embodiment, the two lateral edges 113 and 115 are straight, and theincluded angle is an angle less than 180 degree.

In one embodiment, the sealant 40 is applied on the first substrate 10along a path with a non-rectangular shape. The path includes a number ofstraight paths (such as first straight path st1, second straight pathst2, and third straight path st3) and a number of curved paths (such asfirst curved path ct1 and second curved path ct2).

Specifically, during the process of forming the sealant 40, a firststraight segment 41 is formed on the first substrate 10 along the firststraight path st1, wherein the first straight path st1 is parallel tothe lateral edge 111 and spaced apart from the lateral edge 111 by adistance. Afterwards, a curved segment 42 is formed on the firstsubstrate 10 along the first curved path ct1 which is adjacent to theintersection point 112. It should be understood that a “straightsegment” means that this segment of the sealant is formed on a substratealong a straight path. Therefore, its shape is substantially straight.Considering the sealant is fluid, the straight segment may also becalled a substantially straight segment.

Afterwards, a second straight segment 43 is formed on the firstsubstrate 10 along the second straight path st2, wherein the secondstraight path st2 is parallel to the lateral edge 113 and spaced apartfrom the lateral edge 113 by a distance. Afterwards, a curved segment 44is formed on the first substrate 10 along the second curved path ct2which is adjacent to the intersection point 114. Afterwards, a thirdstraight segment 45 is formed on the first substrate 10 along the thirdstraight path st3, wherein the third straight path st3 is parallel tothe lateral edge 115 and spaced apart from the lateral edge 115 by adistance.

The distance between the first, second, and third straight paths st1,st2, st3 and their corresponding lateral edges 111, 113, and 115 may bethe same or different. As shown in FIG. 2, a circle (shown in right handside of FIG. 2) is tangential to the first straight path st1 and thesecond straight path st2, wherein the first curved path ct1 is an arc ofthe circle, and the rotation radius r₁ of the curved path ct1 equals tothe radius of the circle. In addition, a circle (shown in left hand sideof FIG. 2) is tangential to the second straight path st2 and the thirdstraight path st3, wherein the second curved path ct2 is an arc of thecircle, and the rotation radius r₂ of the curved path ct2 equals to theradius of the circle. In other words, the rotation radius of a curvedpath is equal to the radius of curvature of the curved path.

During the process of applying the sealant 40 over the first and thesecond curved paths ct1 and ct2, the movement of a nozzle 70 forapplying the sealant 40 is controlled by a controller (such as robotarm, not shown in the figures). However, in some embodiments of thedisclosure, the nozzle 70 is not moved along the first and the secondcurved paths ct1 and ct2 precisely. On the contrary, the nozzle 70 ismoved along multiple straight lines, and each straight line is connectedby two neighboring nodes on the first curved paths ct1 or the secondcurved path ct2. Additionally, during the movement of the nozzle 70along a straight line between two neighboring nodes, the nozzle 70 moveswith acceleration that varies. Details of the method for moving thenozzle will be described in the descriptions regarding to theembodiments shown in FIGS. 5 and 7. By controlling the movement of thenozzle 70 among the nodes, the sealant 40 is applied on the firstsubstrate 10 with high efficiency. On the other hand, the manufacturingtime required for producing the display panel 1 is reduced.

In the following description, the maximum distance between the straightline connecting two neighboring nodes and its corresponding curved pathis defined as a manufacturing variance. In one embodiment, the curvedpath is an arc. The arc of a circle is constructed by three of thenodes. However, the method of constructing a circle is not limited tothe above mentioned method. In the process of applying the sealant 40over the same curved path, with the increase of the number of nodes, themanufacturing variance is decreased and the shape of the curved segmentis highly compatible with the curved path. In this case, a longermanufacturing time is required. On the contrary, with the decrease ofthe number of nodes, the manufacturing variance is increased and theshape of the curved segment is roughly compatible with the curved path.In this case, however, the sealant 40 can be applied with a shortermanufacturing time.

Therefore, as shown in FIG. 3, the curved path ct has a rotation radiusr. By applying an infinite number of nodes on the curved path ct, amanufacturing variance for applying the sealant would be approximatelyzero. On the other hand, by applying a finite number of nodes on thecurved path ct, a manufacturing variance for applying the sealant wouldbe approximately μ. Then, according to the trigonometry, we can get thefollowing equation:

0<r−r cos(θ/2)≦μ

Then, we define the shortest distance between two neighboring nodes is adistance D. If the manufacturing variance is zero, the distance D wouldbe zero. If the manufacturing variance is μ, according to thetrigonometry, the distance D can be calculated from the followingequations:

$\begin{matrix}{D = {2\; r\; {\sin \left( \frac{\theta}{2} \right)}}} \\{= {2\; r \times \sqrt{\frac{2\; \mu}{r} - \left( \frac{\mu}{r} \right)^{2}}}} \\{= {2\sqrt{\mu \left( {{2\; r} - \mu} \right)}}}\end{matrix}$

According to the above result, we can conclude that, under a fixedmanufacturing variance, the distance D is greater when the rotationradius r is greater. In other words, the distance D may be approximatelyproportional to the square root of the rotation radius r:

D∝√{square root over (r)}

Based on the above relationship, during the manufacturing of the samedisplay panel, if the manufacturing variance is fixed, a larger rotationradius r of the curved path makes a larger distance D.

In one embodiment, a manufacturing variance μ is given, the distance Dmay satisfy the following equation:

0<D≦2μ√{square root over ((2r−μ))}

In one embodiment, a minimum manufacturing variance μ₁ is given and amaximum manufacturing variance μ₂ is given, the distance D may satisfythe following equation:

2√{square root over (μ₁(2r−μ ₁))}<D≦2√{square root over (μ₂(2r−μ ₂))}

However, the manufacturing variance may be varied in different regionsof the non-display area of the display panel. Therefore, under avariable manufacturing variance, a larger rotation radius r does notnecessarily result in a larger distance D.

In some embodiments, to avoid the display area AA being affected by thecurved segment of the sealant, or to avoid the sealant leaking outsideof the first substrate 10, the manufacturing variance for applying thecurved segment of the sealant 40 is determined based on the distance dbetween the display area AA and the edge of the substrate. For example,as shown in FIG. 2, the lateral edge 111 of the display panel 1 isspaced apart from the edge 120 of the display area AA by a distance d₁,and the lateral edge 115 of the display panel 1 is spaced apart from theedge 120 of the display area AA by a distance d₂, wherein the distanced₂ is equals to the distance d₁. Therefore, the manufacturing variancefor applying the curved segment 42 of the sealant 40 is substantiallythe same as the manufacturing variance for applying the curved segment44 of the sealant 40. In some embodiments, a sealant comprises multiplecurved segments and the one curved segment having the biggest rotationradius r may satisfy the above equation.

In some embodiments, the manufacturing variance for applying the curvedsegment of the sealant equals to the distance d between the lateral edgeof the substrate and the edge of the display area AA. Or, the value ofthe manufacturing variance may be adjusted according to differentrequirements of the display panel. For example, the manufacturingvariance may be 10 μm, 50 μm, 100 μm, 150 μm, or 200 μm, but thedisclosure should not be limited thereto. According to the presetmanufacturing variance, the operator determines the number of node forapplying the sealant on the corresponding curved path. In cases wherethe distance d between the lateral edge of the substrate and the edge ofthe display area AA is selected as the manufacturing variance, thedistance D between two neighboring nodes may satisfy the followingequation:

0<D≦2√{square root over (d(2r−d))}

In one embodiment, a minimum manufacturing variance is 10 μm and amaximum manufacturing variance is 200 μm. Then, the distance D satisfiesthe following range:

2√{square root over (10(2r−10))}≦D≦2√{square root over (200(2r−200))}

wherein r and D in unit of micrometer

FIG. 4 is a flow chart illustrating a method 5 for applying the curvedsegment 42 of the sealant 40, in accordance with some embodiments. Forillustration, the flow chart will be described along with the schematicviews shown in FIG. 5. Some of the steps described in FIG. 4 can bereplaced or eliminated for different embodiments.

Method 5 for applying the curved segment 42 of the sealant 40 isdescribed below:

The method 5 begins with step 50, in which sealant material is appliedby the nozzle 70. In step 51 the speed of the nozzle 70 is decreasedwith a negative acceleration a1. In addition, as shown in FIG. 5, thenozzle 70 is moved from an initial point n0 of the curved segment 42 toa node na1 at the first curved path ct1 which is immediately adjacent tothe initial point n0. During this process, sealant material iscontinuously supplied from the nozzle 70 and is applied on the firstsubstrate 10, and the speed of the nozzle 70 gradually decreases from apreset speed V0 at which the nozzle 70 is moved to apply the straightsegment 41. As a result, the width of the sealant gradually increases towidth B. In some embodiments, when the nozzle 70 reaches the node na1,the speed of the nozzle 70 is 0. In some embodiments, when the nozzle 70reaches the node na1, the speed of the nozzle 70 is still greater than0.

In some embodiments, before applying the curved segment 42, the nozzle70 is moved along the first straight path st1 at the preset speed V0,and the sealant material is supplied from the nozzle 70 at a fixed flowrate to form the straight segment 41 of the sealant 40 on the firstsubstrate 10, wherein the width of the straight segment 41 of thesealant 40 is A. In some embodiments, the nozzle 70 is moved from theinitial point n0 of the curved segment 42 to the node na1 along thefirst straight path st1.

In step 52, the speed of the nozzle 70 is increased with a positiveacceleration a2. In addition, as shown in FIG. 5, the nozzle 70 is movedfrom the node na1 to a middle point of a straight line S1 between thenode na1 and the node na2. During this process, sealant material iscontinuously supplied from the nozzle 70 and is applied on the firstsubstrate 10, and the speed of the nozzle 70 gradually increases. As aresult, the width of the sealant gradually decreases to width C.

In some embodiments, the nozzle 70 reaches the middle point of thestraight line S1 at speed V1, and the speed V1 is greater than the speedV0 at which the nozzle 70 is moved to apply the straight segment 41.Alternatively, the nozzle 70 reaches the middle point of the straightline S1 at speed V1, and the speed V1 is less than the speed V0 at whichthe nozzle 70 is moved to apply the straight segment 41. Alternatively,the nozzle 70 reaches the middle point of the straight line S1 at speedV1, and the speed V1 equals to the speed V0 at which the nozzle 70 ismoved to apply the straight segment 41. In some embodiments, the step 52terminates as the nozzle 70 reaches a position behind or ahead of themiddle point of the straight line S1.

In step 53, the speed of the nozzle 70 is decreased with a negativeacceleration a3. In addition, as shown in FIG. 5, the nozzle 70 is movedfrom the middle point of the straight line S1 to the node na2 along thestraight line S1. During this process, sealant material is continuouslysupplied from the nozzle 70 and is applied on the first substrate 10,and the speed of the nozzle 70 gradually decreases. As a result, thewidth of the sealant gradually increases again.

In some embodiments, the nozzle 70 is moved at the acceleration a1 andthe acceleration a3 for the same time period, and the acceleration a1equals to the acceleration a3. Therefore, the sealant at the node na2has the same width B as the sealant at the node na1; however, thedisclosure should not be limited thereto. In some other embodiments, theacceleration a1 is different from the acceleration a3, and thus thewidth of the sealant 40 at the node na1 is different from the width ofsealant at the node na2.

Afterwards, the sealant material is applied on the first substrate 10along a straight line between the nodes na2 and na3, and along astraight line between the nodes na3 and na4, and along a straight linebetween the nodes na4 and na5 by the method similar to the steps 52 and53.

In step 54, the speed of the nozzle 70 is increased with a positiveacceleration a2. In addition, as shown in FIG. 5, the nozzle 70 is movedfrom the node na5 to an end point n1 of the curved segment 42 along thesecond straight path st2. During this process, sealant material iscontinuously supplied from the nozzle 70 and is applied on the firstsubstrate 10, and the speed of the nozzle 70 gradually increases. As aresult, the width of the sealant gradually decreases. In someembodiments, the step 54 is not stopped until the speed of the nozzle 70is increased to the preset speed V0 at which the nozzle 70 is moved toapply the straight segment 41.

In the above-mentioned embodiments, the nodes na1-na5 are separated bythe same distance D₁, and the distance D between the two neighboringnode centers may satisfy the following equation:

0<D ₁≦2√{square root over (μ₁(2r ₁−μ₁))}

where r₁ is the rotation radius of the first curved path ct1, μ₁ is themanufacturing variance utilized for applying the curved segment 42. Inone embodiment, If the manufacturing variance μ₁ is substituted with thedistance d₁ between the lateral edge 111 of the substrate and the edgeof the display area AA, the distance D₁ may satisfy the followingequation:

0<D ₁≦2√{square root over (d ₁(2r ₁ −d ₁))}

In one embodiment, If the manufacturing variance μ₁ is substituted withthe distance 200 μm, the distance D₁ may satisfy the following equation:

0<D ₁≦2√{square root over (200(2r ₁−200))}

wherein r₁ and D₁ in unit of micrometer

Further, If a minimum manufacturing variance is substituted with thedistance 10 μm, the distance D₁ may satisfy the following equation:

2√{square root over (10(2r ₁−10))}<D ₁≦2√{square root over (200(2r₁−200))}

wherein r₁ and D₁ in unit of micrometer

In some embodiments, the curved segment 42 defines one sealant node 421at each of the nodes na1-na5. Each of the sealant nodes 421 is locatedwithin a range of a circle-like shape and the width of each sealant node421 changes in a narrow-wide-narrow manner. For example, as shown inFIG. 5, the width of the sealant node 421 changes in a A-B-C manner,wherein the width B is greater than the width A as well as the width C.The centers of the sealant nodes 421 are respectively located at thenodes na1-na5, and the radius of the sealant node 421 is smaller than0.5 times of the distance D₁. In addition, the curved segment 42 definesa connection portion 423 between the two neighboring nodes 421. Thesealant node 421 has a larger width of B and the connection portion 423has a smaller width of C. The width B is greater than the width A of thestraight segment 41, and the width A of the straight segment 41 isgreater than or equals to the width C of the connection portion 423. Insome embodiments, the widths A, B, and C are respectively measured in adirection perpendicular to the first curved path ct1.

FIG. 6 is a flow chart illustrating a method 6 for applying the curvedsegment 44 of the sealant 40, in accordance with some embodiments. Forillustration, the flow chart will be described along with the schematicviews shown in FIG. 7. Some of the steps described in FIG. 6 can bereplaced or eliminated for different embodiments.

Method 6 for applying the curved segment 44 of the sealant 40 isdescribed below:

The method 6 begins with step 60, in which sealant material is appliedby the nozzle 70. In step 61, the speed of the nozzle 70 is decreasedwith a negative acceleration a1. In addition, as shown in FIG. 7, thenozzle 70 is moved from an initial point n2 of the curved segment 44 toa node nb1 at the second curved path ct2 which is immediately adjacentto the initial point n2. During this process, sealant material iscontinuously supplied from the nozzle 70 and is applied on the firstsubstrate 10, and the speed of the nozzle 70 gradually decreases from apreset speed V0 at which the nozzle 70 is moved to apply the straightsegment 43. As a result, the width of the sealant gradually increases towidth B. In some embodiments, when the nozzle 70 reaches the node nb1,the speed of the nozzle 70 is 0. In some embodiments, when the nozzle 70reaches the node nb1, the speed of the nozzle 70 is still greater than0.

In some embodiments, before applying the curved segment 44, the nozzle70 is moved along the second straight path st2 at the preset speed V0,and the sealant material is supplied from the nozzle 70 in a fixed flowrate to form the straight segment 43 of the sealant 40 on the firstsubstrate 10, wherein the width of the straight segment 43 of thesealant 40 is A. In some embodiments, the nozzle 70 is moved from theinitial point n2 of the curved segment 44 to the node nb1 along thesecond straight path st2.

In step 62, the speed of the nozzle 70 is increased with a positiveacceleration a2. In addition, as shown in FIG. 7, the nozzle 70 is movedfrom the node nb1 to a middle point of a straight line S2 between thenode nb1 and the node nb2. During this process, sealant material iscontinuously supplied from the nozzle 70 and is applied on the firstsubstrate 10, and the speed of the nozzle 70 gradually increases. As aresult, the width of the sealant gradually decreases to width D.

In some embodiments, the nozzle 70 reaches the middle point of thestraight line S2 at speed V2, and the speed V2 is greater than the speedV0 at which the nozzle 70 is moved to apply the straight segment 43.Alternatively, the nozzle 70 reaches the middle point of the straightline S2 at speed V2, and the speed V2 equals to the speed V0 at whichthe nozzle 70 is moved to apply the straight segment 43. Alternatively,the nozzle 70 reaches the middle point of the straight line S2 at speedV2, and the speed V2 is less than the speed V0 at which the nozzle 70 ismoved to apply the straight segment 41. In some embodiments, the step 62terminates as the nozzle 70 reaches a position behind or ahead of themiddle point of the straight line S2.

In step 63, the speed of the nozzle 70 is decreased with a negativeacceleration a3. In addition, as shown in FIG. 7, the nozzle 70 is movedfrom the middle point of the straight line S2 to the node nb2 along thestraight line S2. During this process, sealant material is continuouslysupplied from the nozzle 70 and is applied on the first substrate 10,and the speed of the nozzle 70 gradually decreases. As a result, thewidth of the sealant gradually increases again.

In some embodiments, the nozzle 70 is moved at the acceleration a1 andthe acceleration a3 for the same time period, and the acceleration a1equals to the acceleration a3. Therefore, the sealant at the node nb2has the same width B as the sealant at the node nb1; however, thedisclosure should not be limited thereto. In some other embodiments, theacceleration a1 is different from the acceleration a3, and thus thewidth of sealant at the node nb1 is different from the width of thesealant at the node nb2.

Afterwards, the sealant material is applied on the first substrate 10along a straight line between the nodes nb2 and nb3, and along astraight line between the nodes nb3 and nb4, and along a straight linebetween the nodes nb4 and nb5 by the method similar to the steps 62 and63.

In step 64, the speed of the nozzle 70 is increased with a positiveacceleration a2. In addition, as shown in FIG. 7, the nozzle 70 is movedfrom the node nb5 to an end point n3 of the curved segment 44 along thethird straight path st3. During this process, sealant material iscontinuously supplied from the nozzle 70 and is applied on the firstsubstrate 10, and the speed of the nozzle 70 gradually increases. As aresult, the width of the sealant gradually decreases. In someembodiments, the step 64 is not stopped until the speed of the nozzle 70is increased to the preset speed V0 at which the nozzle 70 is moved toapply the straight segment 43.

In the above-mentioned embodiments, the nodes nb1-nb5 are separated bythe same distance D₂, and the distance D₂ between the two neighboringnode may satisfy the following equation:

0<D ₂≦2√{square root over (μ₂(2r ₂−μ₂))}

where r₂ is the rotation radius of the second curved path ct2, μ₂ is themanufacturing variance utilized for applying the curved segment 44. Ifthe manufacturing variance μ₂ is substituted with the distance d₂between the lateral edge 115 of the substrate and the edge of thedisplay area AA, the distance D₂ may satisfy the following equation:

0<D ₂≦2√{square root over (d ₂(2r ₂ −d ₂))}

In one embodiment, If the manufacturing variance μ₂ is substituted withthe distance 200 μm, the distance D₂ may satisfy the following equation:

0<D ₂≦2√{square root over (200(2r ₂−200))}

wherein r₂ and D₂ in unit of micrometer

In some embodiments, the curved segment 44 defines one sealant node 441at each of the nodes nb1-nb5. Each of the sealant nodes 441 is locatedwithin a range of a circle-like shape and the width of each sealant node441 changes in a narrow-wide-narrow manner. The centers of the sealantnodes 441 are respectively located at the nodes na1-na5, and the radiusof the sealant nodes 441 is smaller than 0.5 times of the distance D₂.In addition, the curved segment 44 defines an overlapping portion 443 atwhich the two neighboring sealant nodes 441 overlap. The sealant node441 has a larger width B and the overlapping portion 443 has a smallerwidth D. The width B is greater than the width A of the straight segment41. The width A of the straight segment 41 is smaller than the width D.In some embodiments, the width A of the straight segment 41 is equal toor larger than the width D. In some embodiments, the widths A, B, and Dare measured in a direction perpendicular to the second curved path ct2.

Referring to FIG. 2 and with reference to FIGS. 4 and 6, in someembodiments, the manufacturing variances for applying the first curvedsegment 42 and the second curved segment 44 are assumed to be the samevalue. Therefore, according to the following equation:

D∝√{square root over (r)}

The rotation radius r₂ of the second curved path ct2 is smaller than therotation radius r₁ of the first curved path ct1, so the distance D₂between two neighboring sealant nodes 441 is smaller than the distanceD₁ between two neighboring sealant nodes 421. Namely, under the samemanufacturing variance, the rotation radius r₁ and the rotation radiusr₂ may satisfy the relation of 0<r₂/r₁<1, and the distance D₁ and thedistance D₂ may satisfy the relation of 0<D₂/D₁<1.

FIG. 8 shows a schematic view of the sealant 40, in accordance with someembodiments. In some embodiments, the sealant 40 further includes acurved segment 46. The curved segment 46 includes a number of sealantnodes 461, and the sealant nodes 461 have their node nc1-nc5 arranged ona third curved path ct3. In addition, the curved segment 46 includes anumber of connection portions 463 positioned between the two neighboringsealant nodes 461.

In some embodiments, the maximum distance between the outer edge 4612 ofthe sealant node 461 (i.e., an edge of the sealant node 461 which isaway from the display area AA) and the third curved path ct3, is greaterthan the maximum distance between the inner edge 4614 of the sealantnode 461 (i.e., an edge of the sealant node 461 which is close to thedisplay area AA) and the third curved path ct3.

Specifically, as shown in FIG. 8, the outer edge 4612 the sealant node461 includes a first end point p1, a second end point p2, and a thirdend point p3, wherein the first and the second end points p1 and p2 areseparated by a predetermined distance, and the second and the third endpoints p2 and p3 are separated by the same predetermined distance.Moreover, the inner edge 4614 of the sealant node 461 includes a fourthend point p4, a fifth end point p5, and a sixth end point p6, whereinthe fourth and the fifth end points p4 and p5 are separated by thepredetermined distance, and the fifth and the sixth end points p5 and p6are separated by the predetermined distance. In the embodiment, an areaenclosed by the first end point p1, the second end point p2, and thethird end point p3 is greater than an area enclosed by the fourth pointp4, the fifth point p5, and the sixth point p6. In more detail, an areaenclosed by connection lines between an arbitrary two of the first pointp1, the second point p2, and the third point p3, is greater than an areaenclosed by connection lines between an arbitrary two of the fourthpoint p4, the fifth point p5, and the sixth point p6.

In some embodiments, the inner edge 4614 of the node 461 is closer tothe third curved path ct3 than the neighboring connection portion 463.Namely, the distance between the inner edge 4614 of the node 461 and thethird curved path ct3 is smaller than the distance between theconnection portion 463 and the third curved path ct3.

In the embodiment shown in FIG. 8, due to the feature that the inneredge 4614 of the curved segment 46 is closer to the third curved pathct3 than the outer edge 4612, the over-flow of the sealant 46 in thedisplay area AA will not occur. As a result, the adverse effect on thedisplay panel 1 resulting from the sealant is avoided.

FIG. 9 shows an image of a display panel if observed with an opticalmicroscope, in accordance with some embodiments. The display panel ifincludes a first substrate 10 f and a sealant 40 f A curved segment 42 fof the sealant 40 f is located between a straight segment 41 f and astraight segment 43 f.

A method for determining nodes along a curved path ct6 of the sealant 40f is described below. But the method is not limited thereto.

Firstly, create a connection line L1 by connecting any two width centers411 f and 412 f of the straight segment 41 f. Afterwards, create aconnection line L2 by connecting any two width centers 431 f and 432 fof the straight segment 43 f. Afterwards, find a point I1 at theintersection of the connection line L1 and the connection line L2. Notethat the width center of the straight segment is positioned at a half ofthe width of the straight segment.

Afterwards, find a sealant node 421 f at the curved segment 42 f. Thesealant node 421 f is a structure positioned immediately adjacent to thestraight segment 41 f along the application direction of the sealant 40and has a width arranged in a narrow-wide-narrow manner. Afterwards,create a connection line L3 passing through an outer convex point p7 andperpendicular to the connection line L1, wherein the outer convex pointp7 of the sealant node 421 f is a point at the outer edge of the sealantnode 421 f which is farthest from connection line L1. Afterwards, find anode nf1 at the intersection of the connection line L3 and theconnection line L1. The node nf1 is one of the nodes along the curvedpath ct6 and corresponds to the center of the sealant node 421 f.Afterwards, make a circle with a center at the point I1 and with aradius which is equal to the distance between the point I1 and the nodenf1, and find another node nf5 at the intersection of the circle and theconnection line L2. The node nf5 is one of the nodes along the curvedpath ct6 and corresponds to the center of the sealant node 425 f.

A method for determining the rotation center c6 of the curved path ct6on which the node nf1 and the node nf5 are located is described below.But the method is not limited thereto. Firstly, create a connection lineL4 passing through the node nf1 and perpendicular to the connection lineL1. Afterwards, create a connection line L5 passing through the node nf5and perpendicular to the connection line L2. Afterwards, find a rotationcenter c6 of the curved path ct6 at the intersection of the connectionline L4 and the connection line L5. The distance r₆ between the rotationcenter c6 and the node nf1 is equals to the distance r₆ between therotation center c6 and the node nf5, and the distance r₆ is defined asthe rotation radius of the curved path ct6, as well as the rotationradius of the curved segment 42 f

A method for determining the distance D₆ between the two neighboringnodes nf1 and nf2 is described below. But the method is not limitedthereto. Firstly, find a sealant node 422 f at the curved segment 42 f.The sealant node 422 f is a structure positioned immediately adjacent tothe sealant node 421 f along the application direction of the sealant 40and has a width arranged in a narrow-wide-narrow manner. Afterwards,create a connection line L6 between an outer convex point p8 of thesealant node 422 f and the rotation center c6. The outer convex point p8is located at the intersection of the outer edge of the sealant node 422f and a circle with a center at the rotation center c6. In other words,the outer convex point p8 is a point of the outer edge of the sealantnode 422 f which is tangential to the circle.

Afterwards, make a circle with a center at the rotation center c6 andwith a radius which is equal to the rotation radius r₆ so as todetermine the curved path ct6. Afterwards, find a node nf2 at theintersection of the connection line L6 and the curved path ct6. The nodenf2 is corresponding to the center of the sealant node 422 f. Thedistance D₆ is equal to the linear distance between the node nf1 and thenode nf2. And the distance D₆ is equal to the linear distance betweenthe sealant node 421 f and the sealant node 422 f However, the methodfor determining the node nf2 should not be limited to theabove-mentioned embodiment. In some embodiments, the node nf2 is ageometrical center of the sealant node 422 f.

In the embodiment shown in FIG. 9, the distance d between the edge ofthe substrate 10 f and an edge of the display area AA is equal to theshortest distance between an edge of the substrate 10 f and an edge ofthe display area AA. The edge of the substrate 10 f is bounded betweenan intersection of the connection line L4 and the edge of the substrate10 f and another intersection of the connection line L5 and the edge ofthe substrate 10 f. But the present disclosure is not limit thereto.

FIG. 10 shows an image of a display panel 1 g observed with an opticalmicroscope, in accordance with some embodiments. The display panel 1 gincludes a first substrate 10 g and a sealant 40 g. A curved segment 42g of the sealant 40 g is located between a straight segment 41 g and astraight segment 43 g.

A method for determining nodes along the curved path ct7 of the sealant40 g is described below. But the method is not limited thereto.

Firstly, create a connection line L7 by connecting any two width centers411 g and 412 g of the straight segment 41 g. Afterwards, create aconnection line L8 by connecting any two width centers 431 g and 432 gof the straight segment 43 g. Afterwards, find a point 12 at theintersection of the connection line L7 and the connection line L8. Notethat the width center of the straight segment is positioned at a half ofthe width of the straight segment.

Afterwards, find a sealant node 421 g at the curved segment 42 g. Thesealant node 421 g is a structure positioned immediately adjacent to thestraight segment 41 g along the application direction of the sealant 40and has a width arranged in a narrow-wide-narrow manner. Afterwards,create a connection line L9 passing through an outer convex point p9 andperpendicular to the connection line L7, wherein the outer convex pointp9 of the sealant node 421 g is a point at the outer edge of the sealantnode 421 g which is farthest from connection line L7. Afterwards, find anode ng1 at the intersection of the connection line L7 and theconnection line L9. The node ng1 is one of the nodes along the curvedpath ct7 and corresponds to the center of the sealant node 421 g.Afterwards, make a circle with a center at the point 12 and with aradius which is equal to the distance between the point 12 and the nodeng1, and find another node ng4 at the intersection of the circle and theconnection line L2. The node ng4 is one of the nodes along the curvedpath ct7 and corresponds to the center of the sealant node 424 g.

A method for determining the rotation center c7 of the curved path ct7on which the node ng1 and the node ng4 are located is described below.But the method is not limited thereto. Firstly, create a connection lineL10 passing through the node ng1 and perpendicular to the connectionline L7. Afterwards, create a connection line L11 passing through thenode ng4 and perpendicular to the connection line L8. Afterwards, find arotation center c7 of the curved path ct7 at the intersection of theconnection line L10 and the connection line L11. The distance r₇ betweenthe rotation center c7 and the node ng1 is equal to the distance r₇between the rotation center c7 and the node ng4, and the distance r₇ isdefined as the rotation radius of the curved path ct7, as well as therotation radius of the curved segment 42 g.

A method for determining the distance D₇ between the node ng1 and thenode ng2 is described below. But the method is not limited thereto.Firstly, find a sealant node 422 g next to the sealant node 421 g. Thesealant node 422 g is a structure positioned immediately adjacent to thesealant node 421 g along the application direction of the sealant 40 andhas a width arranged in a narrow-wide-narrow manner. Afterwards, createa connection line L12 between an outer convex point p10 of the sealantnode 422 g and the rotation center c7. The outer convex point p10 islocated at an intersection of the outer edge of the sealant node 422 gand a circle with a center at the rotation center c7. In other words,the outer convex point p10 is a point of the outer edge of the sealantnode 422 f which is tangential to the circle.

Afterwards, make a circle with a center at the rotation center c7 andwith a radius which is equal to the rotation radius r₇ so as todetermine the curved path ct7. Afterwards, find a node ng2 at theintersection of the connection line L12 and the curved path ct7. Thenode ng2 is corresponding to the center of the sealant node 422 g. Thedistance D₇ is equal to the linear distance between the node ng1 and thenode ng2. And the distance D₇ is equal to the linear distance betweenthe sealant node 421 g and the sealant node 422 g. However, a method fordetermining the node center ng2 should not be limited to theabove-mentioned embodiment. In some embodiments, the node ng2 is ageometrical center of the sealant node 422 g.

In the embodiment shown in FIG. 10, the distance d between the edge ofthe substrate 10 g and an edge of the display area AA is equal to theshortest distance between an edge of the substrate 10 g and an edge ofthe display area AA. The edge of the substrate 10 g is bounded betweenan intersection of the connection line L10 and the edge of the substrate10 g and another intersection of the connection line L11 and the edge ofthe substrate 10 g. But the present disclosure is not limit thereto.

FIG. 11 shows a schematic view of a display panel 1 d, in accordancewith some embodiments. The display panel 1 d includes a first substrate10 d and a sealant 40 d. In the embodiment, the first substrate 10 d hasan elliptical shape, and the sealant 40 d is applied on the substrate 10d along the edge of the first substrate 10 d.

In some embodiments, in the vicinity of two ends of the minor axis ofthe first substrate 10 d, the sealant 40 d includes a first curvedsegment 42 d. The first curved segment 42 d is applied along the nodesnd1, nd2, and nd3 that are arranged on the first curved path ct4. Thetwo neighboring nodes nd1, nd2, and nd3 are separated from one anotherby a distance D₄, and the first curved path ct4 has a rotation radius r₄and a rotation center c4.

In the vicinity of two ends of the major axis of the first substrate 10d, the sealant 40 d includes a second curved segment 44 d. The secondcurved segment 44 d is applied along the nodes ne1, ne2, and ne3arranged on the second curved path ct5. The two neighboring node centerne1, ne2, and ne3 is separated from one the other by a distance D₅, andthe second curved path ct5 has a rotation radius r₅ and a rotationcenter c5.

In some embodiments, under a condition that the manufacturing variancefor applying the first curved segment 42 d is the same as that forapplying the second curved segment 44 d. The rotation radius r₅ issmaller than the rotation radius r₄. Therefore, according to thefollowing equation:

d∝√{square root over (r)}

The distance D₅ would be smaller than the distance D₄. Namely, therotation radius r₄ and the rotation radius r₅ may satisfy the relationof 0<r₅/r₄<1, and the distance D₄ and the distance D₅ may satisfy therelation of 0<D₅/D₄<1.

Though the sealant nodes of the sealant 40 d are not shown, the distancebetween two neighboring nodes is equal to the distance between the twoneighboring sealant nodes. Similarly, the rotation radius of the curvedpath is equal to the rotation radius of the curved segment.

FIG. 12 shows an image of a display panel 1 h observed with an opticalmicroscope, in accordance with some embodiments. The display panel 1 hincludes a first substrate 10 h and a sealant 40 h. The sealant 40 h isapplied along a curved path ct8 to form a curved segment 42 h.

A method for determining the rotation center c8 of the curved path ct8on which the nodes nh1 and nh2 are located is described below. But themethod is not limited thereto. Firstly, randomly select two points v1and v2 at an inner edge of the sealant node 421 h and create a centralvertical line L13. Afterwards, randomly select two points v3 and v4 atthe inner edge of the sealant node 421 h and create a central verticalline L14. Find a point 13 at an intersection of the central verticallines L13 and L14. Afterwards, make a circle with a center at the point13 and make the circle approach the inner edge of the sealant node 421h. The circumference of the circle and the inner edge of the sealantnode 421 h meet at two farthest points v5 and v6. A radius centralvertical line L15 is obtained by connecting the two points v5 and v6.Afterwards, obtain another radius central vertical line L16 on anothersealant node 422 h using the same method. An intersection of the tworadius central vertical lines L15 and L16 is the rotation center c8. Thedistance r₈ between the rotation center c8 and the curved path ct8 isdefined as the rotation radius of the curved path ct8, as well as therotation radius of the curved segment 42 h.

A method for determining the distance D₈ between the node nh1 and thenode nh2 is described below. Firstly, find a sealant node 422 h next tothe sealant node 421 h. The node nh1 is located on the radius centralvertical line L15 and located at a half of the width of the sealant node421 h. The node nh1 is located on the radius central vertical line L16and located at a half of the width of the sealant node 422 h. Thedistance D₈ is equal to the linear distance between the node nh1 and thenode nh2. And the distance D₈ is equal to the linear distance betweenthe sealant node 421 h and the sealant node 422 h. However, the methodfor determining the node nh1 and the node nh2 should not be limited tothe above-mentioned embodiment. In some embodiments, the node nh1 is ageometrical center of the sealant node 421 h, and the node nh2 is ageometrical center of the sealant node 422 h.

Embodiments for applying a sealant on a substrate are disclosed. Bycontrolling the parameter (the number of nodes, and distance betweennodes) for applying the sealant, the manufacturing time for applying thesealant is adjustable. Therefore, the display panel is producedsufficiently, and the throughput of the display panel is improved. Inaddition, since the manufacturing variance for applying the sealant iscontrolled within a particular range, the problem of the sealant beingapplied over the display area of the display panel is prevented.

Although the embodiments and their advantages have been described indetail, it should be understood that various changes, substitutions, andalterations can be made herein without departing from the spirit andscope of the embodiments as defined by the appended claims. Moreover,the scope of the present application is not intended to be limited tothe particular embodiments of the process, machine, manufacture,composition of matter, means, methods, and steps described in thespecification. As one of ordinary skill in the art will readilyappreciate from the disclosure, processes, machines, manufacture,compositions of matter, means, methods, or steps, presently existing orlater to be developed, that perform substantially the same function orachieve substantially the same result as the corresponding embodimentsdescribed herein may be utilized according to the disclosure.Accordingly, the appended claims are intended to include within theirscope such processes, machines, manufacture, compositions of matter,means, methods, or steps. In addition, each claim constitutes a separateembodiment, and the combination of various claims and embodiments arewithin the scope of the disclosure.

What is claimed is:
 1. A display panel, comprising: a first substratehaving a display area; a second substrate arranged opposite to the firstsubstrate; a display layer positioned between the first substrate andthe second substrate; and a sealant positioned between the firstsubstrate and the second substrate and outside the display area, whereinthe sealant has an outline and at least one portion of the outline iswavy.
 2. The display panel as claimed in claim 1, wherein the firstsubstrate comprises a first lateral edge, and a width of a part of thesealant in a direction perpendicular to the first lateral edge of thefirst substrate changes in the narrow-wide-narrow manner.
 3. The displaypanel as claimed in claim 2, wherein the first substrate furthercomprises a second lateral edge connected to the first lateral edge viaan intersection point, wherein the part of the sealant is positionedadjacent to the intersection point.
 4. The display panel as claimed inclaim 3, wherein the first substrate further comprises a third lateraledge, wherein the first lateral edge, the second lateral edge and thethird lateral edge are straight, and a first included angle formedbetween the first lateral edge and the second lateral edge is less thana second included angle formed between the second lateral edge and thethird lateral edge.
 5. The display panel as claimed in claim 1, whereinthe sealant extends along a path, and a width of a part of the sealantin a direction perpendicular to the path changes in a narrow-wide-narrowmanner.
 6. The display panel as claimed in claim 5, wherein the pathcomprises a first straight path, a curved path, and a second straightpath, the curved path is between the first straight path and the secondstraight path, and the part of the sealant extends along the curvedpath.
 7. The display panel as claimed in claim 1, wherein the sealantcomprises a first straight segment, a curved segment and a secondstraight segment, and the curved segment is between the first straightsegment and the second straight segment.
 8. The display panel as claimedin claim 7, wherein the at least one portion of the outline ispositioned corresponding to the curved segment.
 9. The display panel asclaimed in claim 1, wherein the at least one portion of the outline ispositioned adjacent to a lateral edge of the first substrate.
 10. Thedisplay panel as claimed in claim 1, wherein the at least one portion ofthe outline is positioned adjacent to the display layer.
 11. The displaypanel as claimed in claim 1, wherein the sealant comprises: a firstcurved segment; and a second curved segment; wherein the first curvedsegment has a first rotation radius (r1) and the second curved segmenthas a second rotation radius (r2); wherein the first rotation radius(r1) is greater than the second rotation radius (r2).
 12. The displaypanel as claimed in claim 11, wherein the first rotation radius (r1) andthe second rotation radius (r2) satisfy the equation: 0<r2/r1<1.